Microscopic 'vacuum tubes' could power the computers of the future

 

Vacuum tube technology is making a comeback, with physicists hoping to use miniature 'vacuum transistors' to make increasingly-smaller computers.

 

The development comes just as the laws of physics are seemingly about to catch up with "Moore's Law"—Intel co-founder Gordon Moore's observation that the number of transistors per square inch doubles every two years.

Since the 1980's, technological advancements have enabled scientists to follow Moore's Law. However, this trend is expected to reach an impasse when existing miniaturization techniques no longer prove effective—which may be as soon as the end of this decade.
 

Good old vacuum tubes to the rescue!

 

Well, not quite vacuum tubes, but researchers at the National Aeronautics and Space Administration are coming up with something based on the ancient vacuum tube technology, tech site Gizmodo reported.

 

Citing a report in IEEE Spectrum, the site said transistors that have a small vacuum can draw electrons through themselves without needing an internal physical connection.

 

"Shrink the vacuum space right down, decrease the voltage and it turns out you actually get an incredibly efficient little device," it said.

 

With this technique, Gizmodo said NASA researchers claim to create vacuum transistors that work at the 460 GHz, and mitigate quantum tunneling and electromigration, which could make it hard to make modern transistors much smaller.

 

Coming full circle

 

In a twist of historical irony, vacuum tubes that ran hot and were more prone to failure were replaced by transistors, HotHardware.com said.

 

But now, we have reached the limits of manufacturing technology and "hit the limits of perfection," it said.

 

"We need perfect feature sizes at sizes so tiny, we can't build a laser small enough to etch them. We need to control the level of dopants (deliberate impurities in the silicon substrate) to within 10s of atoms," it said.

 

Things have now seemingly come full circle, as shrinking a vacuum transistor can recover some of the benefits of a vacuum tube minus the negatives of their usage.

 

On the other hand, it said such devices are still in the highly experimental stages.

 

"Vacuum transistors aren't going to reinvent computing in the next two to three years, but long term they could emerge as a way to avoid some of the quantum tunneling and electromigration effects that currently challenge modern microprocessors. That's a huge advance for a transistor structure with nothing in between the source and drain," it said. — Joel Locsin/TJD, GMA News